نشریه پژوهش های ماهی شناسی کاربردی
سال سوم شماره 2 (تابستان 1394)

In this study 15 specimens were collected from Ghareso and Gorganrud Rivers (Golestan Province), Goharbaran, Tajan and Sefidrud Rivers in Mazandaran Province. DNA extraction was performed using Phenol-Chloroform method. A partial DNA sequence of Cytochrome b gene (cytb) was used to evaluate genetic diversity. The sequence of Cytochrome b gene was done using specific primers designed based on sequences registered in NCBI GenBank. The diversity of 785 bp of cytb was estimated. Gene sequencing of samples were compared with using MEGA5 and Bioedit7 software. Also, polymorphism or haplotype frequency was evaluated using dnaSp7 software. Results showed that there was low genetic distance equals to 0.001 among all samples and 6 haplotypes among samples were determined. ‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬The most haplotypes were observed in Gorganrud and Ghareso Rivers. The phylogenetic test showed that all the fishes are in a clad.

In order to evaluate and compare the body shape of the bitterling (Rhodeus amarus) in Tajan¡ Babolroud¡ Siahroud rivers and Anzali lagoon using geometric - morphometric and traditional morphometric methods¡ 120 specimens were collected with electrofishing. To compare the traditional morphometric characteristics of the population¡ 29 morphometric characters were measured using digital caliper with 0.01 mm accuracy and 12 meristic characters were counted. Then to compare the geometric morphometric characters of the populations¡ left sides of the specimens were photographed using digital camera and 23 landmark points were digitized on 2D images using TpsDig2. The results were analyzed using MANOVA /CVA and PCA test. After the standardization of the measured characters using the PAST software¡ separating characters and their separation rate were determined via principal component analysis (PCA). For all the meristic factors of the studied populations¡ none have the coefficient factor above 0.8. Also¡ in morphometric characters for pre-anal length¡ head length and head height had coefficient factor above 0.8 in the first component. One-way ANOVA test results revealed that between all the characters¡ except for the characters scales of above lateral line anal and dorsal fin rays¡ body height¡ caudal peduncle length¡ predorsal length and length of anal fin¡ a significant difference was found between other characteristics (p

Reduction of quality and quantity of wild and farm Persian sturgeon in early life cycle is the most important problems in this endemic and economical species. The purpose of this study was to increase the production efficiency of Acipenser persicus in the first feeding stage to fingerling stage using effect reaction between photoperiod and light intensity. This study was conducted with 13 treatments including 4 photoperiod (24L:00D, 16L:08D, 12L:12D and 08L:16D), 3 light intensity (100, 250 and 450 lux) and one control with three repetition in each treatment (each repeated include 1800 larvae with initial weight and length 41.66 mg and 19.64 mm, respectably) during 60 days. During the experimental period, individual body length and weight were taken at the first and 60th day after the first feeding. All of the fish were fed on live food in the same amount. Biological measurements, including final weight, final length, weight gain (WG), specific growth rate (SGR), condition factor (CF), body weight increase (BWI (and Survival rate (SR), were analyzed. The result indicated that except for survival rate, growth factors were subject to the mutual effect of photoperiod and light intensity, although the final weight and length were affected more by the photoperiod. The growth factors of fish that were in 12L:12D photoperiod with an intensity of 100 lux and 08L:16D photoperiod with an intensity of 250lux were significantly better than others photoperiod and light intensity treatments.

This study was conducted to evaluate the effects of enzymes produced by five Bacillus probiotics on growth and nutritional parameters of rainbow trout (Oncorhynchus mykiss) larvae with an initial body weight of 0.53 ± 0.19 g during 60 days. The enzyme suspension produced by Bacillus probitics resulted from culturing the bacilli in broth media with three concentrations of 1×106, 1×107 and 1×108 CFU/100g were inoculated into the diet of rainbow trout larvae. The results of larval biometry at the end of the period of the experiment showed the following: First, the use of enzyme suspension, produced by the highest concentration of Bacillus (1×108 CFU/100g) fed in T3 treatments (20.02 ± 3.77 g), caused a significant increase in the weight growth (P

The outbreak of diseases is a limiting factor in fish farms. A large number of plants are being used in traditional medicine for the treatment and control of diseases. One of such plants is ginger (Zingiber officinale). In this study antimicrobial effects of alcoholic extracts of ginger on six important positive and negative gram bacteria including Vibrio alginolyticus, Vibrio parahemolyticus, Micrococcus luteus, Staphylococcus epidermicus, Bacillus cereus, Stereptococcus zoo epidermicus were analyzed. Extraction was conducted on rhizomes of Ginger using 80% ethanol in laboratory. In order to assess antimicrobial effects of the ginger extract on the studied bacterial species, diffusion test on agar media using disk method on studied bacteria was conducted. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined by serial dilution assay using Liquid culture in 96 wells microplates. Results indicated that ginger alcoholic extracts have inhibitory effects on the bacterial growth and is lethal for all bacterial strains. Also ginger alcoholic extract has the most and the least growth inhibitory and lethal affects on Vibrio alginolyticus and Vibrio parahemolyticus, respectively.

Aquatic environments are hospitalized for contaminants and most fish life is in contact with the water. Due to its resistance, anatomical and physiological similarities to other carp fish, goldfish was chosen in the present study as biological model in order to study the effect of silver nanoparticles on hematological parameters of carps. For the biochemical and hematological tests of the groups under investigation, nine fish were randomly selected from each treatment and were separately exposed to effective concentrations of nano-silver in 0.1, 0.5, 1 and 5 ppm. Measured indices included total number of white blood cells (leukocytes), lymphocytes, neutrophils, eosinophil, total number of red blood cells (erythrocytes), hemoglobin content, hematocrit level, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and serum glucoses. Results showed that different concentrations of nano silver had significant effect on blood erythrocyte factors but not on leukocyte parameters. This may be due to the resistance of goldfish in comparison with the other fish species.

Osteological structures of fishes are valuable characteristics in taxonomic and phenotypic plasticity studies to understand their evolutionary trends. In this regard, isolation of populations can lead to morphological divergence particularly in osteological structures which can result in their differentiation. Hence, this study aimed to describe the osteological features of Waspi Cabdio morar and compare its two allopatric populations inhabiting in Makran and Mashkil basins of Iran. For this purpose, 30 specimens were sampled from each basin. The specimens were fixed into 4% buffered formalin after anaesthetizing and then cleared and stained with alizarin red S and alcian blue for osteological examinations. Then the osteological features of this species were described in detail. The results showed that Sarbaz River population possesses less curved haemal and neural spines compared to those of Mashkil which results in a deeper body shape. Also, the Mashkil population had a deeper caudal peduncle due to bifurcated neural spines. In addition differences in features of parietal, parasphenoid, prevomer and branchial arches were observed. The observed morphological divergence may reflect the emerging evolution in response to environmental factors of their habitat and geographical isolation.

In this study, age and growth of the Stripped Piggy, Pomadasys stridens (Forsskal), in the Persian Gulf (Bushehr coasts) were investigated. A total of 540 samples were obtained from June 2010 to May 2011. Total length of the female fish ranged from 12.6 to 23 cm and the male ones from 11.7 to 22 cm. Also, the weight of the female fishes was ranged from 27.4 to 144.8 gr and in the male fishes from 21 to 124.9 gr. Age groups in both sexes in P. stridens were estimated to be between 1 to 8 years. The weight-length relationships was described as W= 0.0694 L2.4398 (r2=0.86, n=385)for females, W=0.0477 L2.5701 (r2=0.88, n=155) for males and W=0.0617 L2.4804 (r2=0.89) for the total population. According to the obtained values of b, both weight-length relationships for sexes showed a negative allometric growth. Also, parameter values of the Von Bertalanffy growth function were, K=0.14, L∞=24.54cm (TL), t0=-4.41 years for females and K=0.18, L∞=21.91cm (TL), t0=-3.68 for males. The growth performance index (∮) was estimated 4.45 for female and 4.43 for male indicated that the growth rate for female fishes is faster than male fishes.